I have simplified the program some what and speed-ed it
up. I was missing some of the compression  pulses at 10 milliseconds.

Here is the new program with comments.

.
 Cls   '.........................clear the screen

3 Open "press.dat" For output As #1 'open a file on the SD card
'..............................................................upper and lower case does
'...............................................................not matter in MM BASIC.

5 SetPin 9,1  '............set up pin 9 for A 2 D input
6 Print "rotor 1" '......print on the screen
7 Print Date$ '.......print on the screen
8 Print Time$ '........print on the screen

SetTick 10,30  '.....wait until 10 milliseconds has past
'............................and then go do it.

10 'bakgr     '.........twiddle thy thumbs
15 GoTo 10

30
For x = 1 To 8   '....sample & record 8 readings as fast as possible
'.............................probably as often as a few dozen microseconds.

press = Pin(9)
 Print press ;  '.......print on the screen
 Print #1, press; '.....record it
 Print #1, ",";
Next
Print      '..............print a carriage return on the screen
Print #1,  '...........record a carriage return in the file

35 IReturn '......software interrupt return

Here is a picture of the output on the screen.
These numbers need to be doubled because of the
voltage divider. As you can see there are 3 pulse
in a row indicating this rotor is OK.

The numbers data file is an ASCII  or txt file so you need to open it
with word pad. It is zipped because it would display on
your cell phone as one great big long message.

Paul Lamar

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